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arXiv · 1106.4498

Expansion of the Youngest Galactic Supernova Remnant G1.9+0.3

A. K. Carlton·K. J. Borkowski·S. P. Reynolds·U. Hwang·R. Petre·D. A. Green·K. Krishnamurthy·R. Willett
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Abstract

We present a measurement of the expansion and brightening of G1.9+0.3, the youngest Galactic supernova remnant, comparing Chandra X-ray images obtained in 2007 and 2009. A simple uniform expansion model describes the data well, giving an expansion rate of 0.642 +/- 0.049 % yr^-1, and a flux increase of 1.7 +/- 1.0 % yr^-1. Without deceleration, the remnant age would then be 156 +/- 11 yr, consistent with earlier results. Since deceleration must have occurred, this age is an upper limit; we estimate an age of about 110 yr, or an explosion date of about 1900. The flux increase is comparable to reported increases at radio wavelengths. G1.9+0.3 is the only Galactic supernova remnant increasing in flux, with implications for the physics of electron acceleration in shock waves

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A. K. Carlton, K. J. Borkowski, S. P. Reynolds, U. Hwang, R. Petre, D. A. Green, K. Krishnamurthy, R. Willett. 2011-06-22. Expansion of the Youngest Galactic Supernova Remnant G1.9+0.3. https://doi.org/10.1088/2041-8205%2F737%2F1%2Fl22

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